A New Monitor With a Zinc‐Oxide Thin Film Semiconductor Sensor for the Measurement of Volatile Sulfur Compounds in Mouth Air

Abstract

Halitosis, defined as unpleasant oral odor, is a concern among the general public. Halitosis is generally diagnosed by organoleptic examination and by gas chromatographic analysis of the main source of halitosis, volatile sulfur compounds, such as hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. Gas chromatography requires a large-scale system and a long running time. We investigated the use of a zinc-oxide thin film semiconductor sensor for measuring trace volatile sulfur compounds in mouth air. Mouth air samples collected in teflon bags from 21 volunteers were analyzed by 3 methods: the monitor analysis, gas chromatography, and organoleptic examination by 3 judges. The readings of the monitor were correlated with the values of the total volatile sulfur compounds measured by gas chromatography (r = 0.75, P < 0.01) and also with the organoleptic scores given by the judges (r = 0.76, P < 0.01). The organoleptic scores were correlated with the gas chromatographic values (r = 0.71, P < 0.01). These results suggest that this new monitor with a zinc-oxide thin film semiconductor sensor may be used for the diagnosis of halitosis. Its small size and simplicity of handling may enable its use for routine chair-side study and field surveys of halitosis.

Association between oral malodor and measurements obtained using a new sulfide monitor

“…The special filter was developed to trap ketone and alcohol smells in toothpaste, mouth rinse and mouth air, and has been described in more detail in a previous study. 7 It requires 1 min 45 s for warming-up before operation and 45 s for monitoring. The suction rate of air by the VSCs monitor is 50-80 ml/min.…”

“…6 The simplest approach is the organoleptic ratings by human judges. 7 It is considered the gold standard for measuring bad breath, both for the industry and academia. 8 This method closely simulates the everyday situations in which bad breath is detected, but it is subjective and requires trained odor judges whose reliability has been questioned.…”

Prevalence of Halitosis and Evaluation of Etiological Factors in a Turkish Subpopulation

“…The three main methods for measuring and assessing the halitosis are organoleptic measurement, gas chromatography (GC), and sulfide monitoring 13 . Methyl mercaptan, hydrogen sulfide, butyric acid, proprionic acid and valeric acid are called as volatile sulphur components (VSCs) and these components are major cause of halitosis 14 .…”

The use of thin silver films for the detection of low concentrations of hydrogen sulphide

“…Heated tin dioxide thin ®lms have been used [8,9] and zinc oxide has been utilized for the measurement of volatile sulphur compounds in the breath [10]. Recently a gas sensor has been fabricated based on a tin dioxide/copper oxide mixture which showed a maximum in sensitivity and in selectivity at the relatively low operating temperature of 1008C [11].…”